Soy, Glycine max

The soybean is a legume and, alongside maize, rice and wheat, is one of the most important crops, mainly grown for animal feed and oil production. Around 77% of the soy harvest is used as animal feed, making soy the most important source of protein meal worldwide. Soy is grown on almost 8% of the world’s arable land – around half of which comes from South American countries, where monocultures are spreading rapidly at the expense of virgin forest.

Plant with many benefits

The soybean is an annual plant from the legume family, subfamily papilionaceous. It grows herbaceously, with oval, very hairy leaves on thin, branched stems. It grows to a height of between 20 and 80 centimetres, but can also reach well over a meter. The purple or white flowers produce pods about 4 cm long, each containing up to 4 seeds, the soybeans. When the leaves fall off at the end of the season, the soybeans can be harvested.

For optimum growth, soy requires loose and therefore well-aerated soils, which are ideally deep and have a high water storage capacity. As a member of the genus Faboideae, soy has the ability to attach bacteria to its roots, which extract nitrogen from the air. Soy owes its high protein content to this nitrogen, through which it secures its status as a highly sought-after source of energy worldwide.

The road to fourth place – the history of soy

The origins of the soybean plant lie in Asia. Wild soybeans were roasted in northern and north-eastern China as early as 7,000 BC. However, the first evidence of domesticated soybeans comes from Japan and dates back to around 3,000 BC. For thousands of years, cultivation and consumption remained limited to China, Japan, Korea, Taiwan, Mongolia and neighboring parts of Russia. Until the beginning of the Second World War, China was the main cultivation area, accounting for 87% of the global harvest.

The soybean only came to Europe in the early 18th century – as a rarity in botanical gardens after commercial cultivation attempts failed due to the climatic conditions.

Experiments were also carried out in the USA a few decades later – albeit with more success, so that the soy industry began to boom after the First World War – initially with soybean oil in paints and varnishes and for the production of nitroglycerine. Soybean cake as a by-product was used as animal feed. Rapidly growing industrial demand and government-sponsored demand for meat, combined with increasingly mechanised agriculture, led to a sharp increase in soybean acreage in the USA. Due to the supply of palm and coconut oil being cut off during the Second World War, soybean oil found its way into food processing and corresponding government subsidies further accelerated cultivation.

Around the same time, soy experienced an unexpected rise in National Socialist Germany, with IG Farben (a german chemical and pharmaceutical company) playing an important role in the production and procurement of soy from south-eastern European countries – initially for its own production of dyes, then under the Nazi regime as a supervisor for the forced labourers in soy cultivation. Due to its high nutrient content, soy was to make a decisive contribution to the food supply during the Second World War. Foods specially developed for the Wehrmacht at the time are once again very popular in vegan nutrition today: spreads, powders for making patties and the first meat substitutes.

After the Second World War, global soybean cultivation developed rapidly. Instead of East Asia, North and South America became the main areas of cultivation. The driving force was the change in animal husbandry and the displacement of other crops such as maize, as the cultivation of soy was more lucrative. In the 1950s, more soy was already being produced in the USA than in the whole of Asia put together.

As of 2022, almost 350 million tons of soya were produced worldwide, with Brazil as the largest soya producer (35%), followed by the USA (33%) and Argentina (13%). Brazil supplies almost all of its domestic production to China.

Use as animal feed and in industry

Soy is mainly used for animal feed and oil production – the proportion of global soy production that flows directly into human nutrition is around 6%. Around 7% of the global soy harvest is used directly as animal feed. The remaining 87% is further processed – into soybean cake (extraction meal) and soybean oil. Around four-fifths of the soybean ends up in soybean cake. This is used as a protein- and nutrient-rich supplementary feed in poultry, pig and cattle farming worldwide. While China, for example, produces its own soy for food, the country is the largest importer of soy and uses its imports mainly as animal feed, especially for pigs (almost a third of the world’s meat production – over 63 kg per capita – is consumed in China).

But what actually makes soybean cultivation profitable? It is widely believed that the extraction meal is merely a waste product of oil production. However, it turns out that more than half of the income from soy production is generated through the sale of animal feed – without factory farming, the cultivation of rainforest and genetically modified soy would simply not be worthwhile. Feed therefore not only accounts for the majority of use in quantitative terms, but is also the more important part economically.

The oil extracted from soybeans is used for industrial purposes in addition to the food industry (around 80% of the oil). Worldwide, around 17% of the oil extracted is used as biofuel every year, particularly in the USA and South America. In contrast to conventional fuels, biodiesel made from soybean oil reduces greenhouse gas emissions considerably during combustion and is probably more effective than corn-based bioethanol. However, the high proportion of agricultural land that is not used for food is problematic – all the more so as the distance a combustion engine can cover with biofuels does little to meaningfully contribute to the amount needed to supply the current demand.

Its use in other industries is also still relevant, for example in the production of paints, varnishes, soaps and cosmetics. For example, almost 50% of American newspapers and magazines are printed with inks based on soybean oil.

Soy as food

The soybean oil pressed from the beans accounts for almost 17% of the global harvest and 80% of it is used by the food industry in around 30,000 different products. Soybean oil is used in the production of margarine, deep-frying fat, mayonnaise and dressings, or as a binding agent and stabiliser in packet soup, chocolate, bread rolls or ice cream. Soybean oil is used to a much lesser extent for cooking and frying. Only around 6% of the soybeans harvested worldwide are processed into other vegan products for direct human consumption – i.e. tofu, soy milk, meat substitutes or sprouts, which are mainly known from Asia.

If you are looking for a balanced diet and want to eat fewer animal products or meat products, soy and soy products are a nutritious and protein-rich alternative. Products containing soy provide the body with more unsaturated fatty acids than meat and sausage products and are completely cholesterol-free. In addition, soybeans contain all the essential amino acids that the body cannot produce itself and must therefore be obtained from food. For this reason, and due to the high protein content, soy products are also a good alternative to chicken and cow’s milk. They also contain minerals such as magnesium and calcium, trace elements, vitamin E and many B vitamins as well as a high content of isoflavones, which are phytoestrogens (secondary plant substances).

Threat to rainforest and population

Due to the enormous demand for soy, huge areas of land are still being developed for soy monocultures. The destruction of South American rainforests in particular, which has been on the rise since the 1960s, has catastrophic consequences for local ecosystems and contributes significantly to rising greenhouse gas emissions worldwide. The same applies to the Cerrado savannah, 50% of which is estimated to have already been destroyed. Systematic deforestation and the increasing use of pesticides are endangering soils, plants and animals, damaging groundwater and causing disease. The lack of vegetation cover is causing the soil to erode and heavy machinery is compacting it, meaning that new land has to be taken over and planted time and time again.

Another problem, particularly in Brazil, Argentina and Paraguay, is the often illegal and violent expropriation of the smallholder and indigenous population. Today, the majority of arable land in these countries is claimed by a few large investors exclusively for the cultivation of soy and supplied with genetically modified seeds (GM soy) by a few large agricultural companies such as Monsanto, DuPont or Bayer. Today, over 90% of the seeds used in the main soybean-growing countries in South America and 97% in the USA are genetically modified.

Originally to increase the yield per hectare, experiments with hybrids have been carried out in the USA since the 1970’s and the first GM soy that was resistant to the weedkiller glyphosate was approved in 1996. However, the herbicide has to be applied in ever higher doses because more and more weed species are becoming resistant to glyphosate, so that today three times more than the original dose has to be applied, and other, even more toxic herbicides are also used. The dangers to the health of the rural population and the environmental damage are currently being accepted in all countries where the crop is grown. Although the cultivation of GM soy is still not permitted in the EU, imported soy is fed to livestock – the health risks for animals and humans have not yet been fully researched.

In order to significantly and immediately reduce the demand for soy, especially from South America, where rainforests are destroyed for its cultivation, turning away from industrial factory farming would be the quickest way to success.

Sources

• Federal Statistical Office
• SODI! Research Report Soy.
• FAO – UN Food and Agriculture Organization
• Fraanje, W. & Garnett, T. (2020). Soy: food, feed, and land use change. (Foodsource: Building Blocks). Food Climate Research Network, University of Oxford. View here.
• Albert Schweitzer Foundation: Does only soy waste end up in animal feed? Read here.